This proposal represents an effort to explain why racial disparities in infant mortality persist despite significant progress in the capacity of health care interventions to influence birth outcome and infant survival. Its primary objective is to link the analysis of the social and demographic determinants of risk with the analysis of social and demographic determinants of technology use and effect. The proposed analysis represents a structured decomposition of the processes by which racial differences in risk status, health care utilization, and most significant, the interaction of enhanced risk and reduced utilization produce racial disparities in infant survival. The determinants of disparities in both neonatal and postneonatal mortality will be examined. The approach outlined in this proposal is intended to make sharp distinction between the causation of infant mortality and the causation of disparities in infant mortality. The proposed project is based upon an analytic model which is directed specifically at the causation of disparities in infant mortality and inherently links differential risk to differential utilization. The analysis utilizes nationally-based, secondary data sets and is comprised of four related components. First, race-specific distributions of demographic, social, behavioral, and clinical factors will be examined in detail to determine their respective singular and interactive associations with birth-weight distribution and birth- weight-specific mortality differentials. Second, racial disparities in the utilization of health care and related interventions will be documented. Third, disparate risk and disparate utilization will be analyzed together to identify specifically the areas of risk- specific utilization disparities that are most critical to shaping inequities in infant mortality. Fourth, the conveyance of elevated risk from one period of fetal/infant growth to another will be assessed, such that estimates can be made of that portion of neonatal or postneonatal mortality that can be attributed to risk- utilization disparities occurring in prior periods. Fifth, the special issue of racial patterns of inherited risk for low birth- weight will be analyzed such that its nature can be assessed in relation to its relevance as a contributor to observed racial disparities in infant survival.